Registration & Submission Deadline
Wednesday, April 10, 2013 @ 11:59 PM
April 23rd & 24th, 2013Claire T. Carney Library Addition
Comparison of Populations of a Recent Marine Invader in 1996 and 2012
Stephen J. Perkins and Dr. Nancy J. O’Connor; Department of Biology
The Asian shore crab Hemigrapsus sanguineus was introduced to the United States Atlantic coast from the North Pacific Ocean. First noticed in New Jersey in 1988, it is now well established in New England. The purpose of this study was to compare densities of the crab in the intertidal zone in 2012 to its intertidal densities in 1996. Sampling was performed during September and November at Gooseberry Island and Sandwich Town Beach at different intertidal elevations. At Gooseberry in September 2012, crabs were present in similar densities at three intertidal heights. In November the crabs moved to the lower intertidal and no crabs were found at the highest elevation, similar to the 1996 study. At Sandwich in September 2012, there were more crabs at lower intertidal heights and few at the highest intertidal height. Sampling in November 2012 took place at a different location due to extreme shoreline change from a hurricane. There were more crabs at the higher than lower intertidal heights, in contrast to the results of the 1996 study. Crab densities at both locations were much higher in 2012 than 1996 showing that H. sanguineus was not well established in 1996.